1. Field of the Invention
This invention relates to electrical switching apparatus such as power circuit breakers, network protectors and switches used in electrical power circuits carrying large currents. More particularly, it relates to the push buttons which operate the apparatus and to a cover plate through which the push buttons are accessible.
2. Background Information
Electrical switching apparatus for opening and closing low voltage electric power circuit typically incorporate an operating mechanism which utilizes an energy storage device in the form of one or more large springs to close the contacts of the device into the large currents which can be drawn in such circuits. Such electrical apparatus includes power circuit breakers and network protectors which provide protection, and electrical switches which are used to energize and deenergize parts of the circuit or to transfer between alternative power sources. These devices also include an opening spring or springs which rapidly separate the contacts to interrupt current flowing in the power circuit. As indicated, either or both of the close spring and open spring can be a single spring or multiple springs and should be considered as either even though the singular is hereafter used for convenience.
The operating mechanisms in these electric power switching devices include close and open push buttons which may be operated to release the springs to close and open the contacts of the switch respectively. Typically these push button are individually mounted. Often they are circular buttons biased outwardly by a helical compression spring and which move linearly inward when depressed to an actuated position. While such push buttons work quite well, there is an interest in push buttons which are easier to manufacture and install and which are less costly.
Typically, the push buttons are aligned with openings in the front of the switch housing. This housing may include a large front cover extending over the operating mechanism and its push buttons. Commonly, the components of the operating mechanism of these power electric switches are supported at multiple points in the switch housing. Due to tolerances, it is difficult to align the push buttons with the access openings.
There is a need therefore, for improved electrical switching apparatus having push buttons which are easier to manufacture and assemble, and are less costly.
There is a related need for such electrical switching apparatus in which the push buttons are more easily aligned for accessibility.